In the Linux kernel, the following vulnerability has been resolved:

firmware: qcom: scm: Fix missing read barrier in qcom_scm_get_tzmem_pool()

Commit 2e4955167ec5 ("firmware: qcom: scm: Fix __scm and waitq
completion variable initialization") introduced a write barrier in probe
function to store global '__scm' variable.  We all known barriers are
paired (see memory-barriers.txt: "Note that write barriers should
normally be paired with read or address-dependency barriers"), therefore
accessing it from concurrent contexts requires read barrier.  Previous
commit added such barrier in qcom_scm_is_available(), so let's use that
directly.

Lack of this read barrier can result in fetching stale '__scm' variable
value, NULL, and dereferencing it.

Note that barrier in qcom_scm_is_available() satisfies here the control
dependency.

https://git.kernel.org/stable/c/b628510397b5cafa1f5d3e848a28affd1c635302

https://git.kernel.org/stable/c/e03db7c1255ebabba5e1a447754faeb138de15a2

https://git.kernel.org/stable/c/fee921e3c641f64185abee83f9a6e65f0b380682